1. Field of the Invention
The invention relates to a power supply with a switch converter which can be connected to an input-side voltage via a positive cable and to a ground potential via a negative cable and comprises a circuit breaker, a storage inductor and a peak current controller.
2. Description of the Related Art
Power supplies with switch converters serve to convert a supply voltage into a desired output voltage. Here, a rectified intermediate circuit voltage is generally converted into a constant output DC voltage.
A common control variant comprises a peak current controller, to which the current is supplied by a storage inductor as an input variable. As soon as the detected inductance current conforms to a predetermined peak value, the circuit breaker is switched off. Here, the circuit breaker is controlled via a pulse width modulation circuit that interacts with the peak current controller.
Known solutions for detecting the current through the storage inductor utilize a shunt resistor arranged in the negative cable. The voltage drop across this shunt resistor serves as a measured variable for the current to be detected, where the resulting measuring signal with respect to the ground potential is present.